McColo was shut down by its ISP on November 11 following a journalist's inquiries about illicit spam activities. Subsequently, the volume of spam around the world fell by as much as 70 percent since command and control servers for three major spam botnets were hosted by McColo.
The Mega-D botnet, famous for sending billions of spam emails promoting sexual performance remedies, along with the Srizbi and Rustock botnets was effectively turned off due to the closure of McColo. The botnet's thousands of infected zombie computers could no longer communicate with the Mega-D command and control servers and ceased spamming.
However, Mega-D's creators have worked constantly over the past three weeks to set up new command and control servers and re-establish connections with their network of compromised bots. According to the TRACElabs spam statistics, the spammers have managed to restore those connections and Mega-D is now back spamming again.
"Spam from Mega-D has been ramping up over the last few days and reached up to 48 percent of all the spam we captured in our honey pot spam traps," said Phil Hay, lead threat analyst for the Marshal8e6 TRACElabs.
Marshal8e6 maintains a Spam Volume Index on its website, tracking the total volume of spam it receives. This index is used to measure fluctuations in global spam volume over time. According to Marshal8e6, the volume of spam has doubled since the low point immediately following the McColo shutdown.
"Many security researchers, including ourselves, predicted that spam volumes were likely to eventually bounce back after McColo's shutdown," said Hay. "Based on what we have seen from Mega-D this week, that seems to be happening now. Spam volumes are still only about 40 percent of where they were in September this year but they have doubled since the last week of November, so the spammers seem to be clawing their way back."
"After McColo was shut down, we observed activity indicating that the individuals behind the Srizbi, Rustock and Mega-D botnets were attempting to set up new command and control servers," Hay continued. "We saw some activity occurring with the Rustock botnet, but it appears to have gone quiet again. Mega-D is the first of the affected botnets to really bounce back. However, it is a changed botnet now. It no longer exhibits some of its previously distinctive characteristics."
"The Mega-D bots appear to have been upgraded and altered quite substantially by the people behind it. It now uses templates we have seen before with Rustock. This is an interesting development. It could mean that the Mega-D spammers have looked at and copied from their rivals. Or, it could indicate that the individuals behind both botnets are working in collusion or are one in the same. This is something that we will explore further," added Hay.
More Information Marshal8e6 TRACE Centre Website - http://www.marshal.com/trace/
About the Marshal8e6 TRACE Team TRACE (Threat Research and Content Engineering) is a group of Marshal8e6 security analysts who constantly monitor and respond to Internet security threats through the TRACE website at www.marshal.com/trace. TRACE services are provided as part of standard product maintenance that includes updates to Marshal8e6's unique, proprietary anti-spam technology, SpamCensor. TRACE analyses spam, phishing and Internet security trends and provides frequent automated updates to Marshal8e6 customers. It also provides "Zero Day" security protection against new email and virus exploits the day they emerge.
About Marshal8e6 Marshal8e6 is a global provider of Secure Internet Gateway products for organizations of all sizes. Marshal8e6 is the only security company capable of delivering comprehensive content security across multiple delivery platforms, including software, appliances and Software-as-a-Service (SaaS). The company's complete security portfolio delivers the tools necessary to manage and secure email, Web and the endpoint as well as protect against data leakage. With 20,000 customers and 16 million end users in 96 countries, the company maintains corporate headquarters in Orange, California with international headquarters in London, United Kingdom, and regional offices in Atlanta, Houston, Johannesburg, Munich, Paris, Auckland, Sydney and Taipei.
Marshal8e6 is privately held by management and employees, as well as private investors Kelso Place Asset Management, Darwin Group, CX Ventures, Vora Ventures and Updata Partners. For more information about Marshal8e6, please visit www.marshal8e6.com.